Patent EP0096638 describes a method for preparing cross-linked bitumen/polymer compositions in particular from a mother solution consisting of a hydrocarbon oil which has a distillation range at atmospheric pressure comprised between 100° C. and 450° C., chosen from the petroleum cuts of aromatic character, petroleum cuts of naphtheno-paraffinic character, petroleum cuts of naphtheno-aromatic character, coal oils and oils of vegetable origin. The quantity of polymer in the mother solution can represent from 5% to 40% of the weight of the hydrocarbon oil. The chemical nature and the physico-chemical characteristics of the oil of vegetable origin are not specified.
Patent EP0582703 describes a method for preparing cross-linked bitumen/polymer compositions from a mother solution consisting of a hydrocarbon oil which has a distillation range at atmospheric pressure comprised between 100° C. and 600° C., chosen from the petroleum cuts of aromatic character, petroleum cuts of paraffinic character, petroleum cuts of naphtheno-paraffinic character, petroleum cuts of naphtheno-aromatic character, coal oils and oils of vegetable origin. The quantity of polymer in the mother solution can represent from 5% to 40% of the weight of the hydrocarbon oil. Once again, the chemical nature and the physico-chemical characteristics of the oil of vegetable origin are not specified.
The application WO2007068461 describes a bituminous binder comprising at least one bitumen, at least one cross-linked or non-cross-linked polymer, fluxed using a flux which is an oil of vegetable origin and in particular, a castor oil methyl ester. The bituminous binder fluxed using this castor oil methyl ester can be prepared from a mother solution comprising at least one cross-linked or non-cross-linked polymer and castor oil methyl ester. The percentage by weight of polymer with respect to the total weight of the mother solution is comprised between 1% and 30%. The Applicant company recognized that a mother solution prepared from an oil of vegetable origin such as that described in the application WO2007068461, i.e. a castor oil methyl ester, is not stable and gels during storage much more rapidly than the mother solutions according to the invention.
The application WO2008077888 describes a bituminous composition fluxed using a flux comprising at least one compound of vegetable origin and at least one hydrocarbon cut originating from the refining of crude oil. The fluxed bituminous composition can be prepared from a mother solution comprising at least one polymer and the flux based on the compound of vegetable origin and on the hydrocarbon cut originating from the refining of crude oil. The proportions by mass of flux and polymer (flux/polymer) in the mother solution vary from 10:90 to 90:10. This mother solution has the drawback of being formulated from a mixture of an oil of petroleum origin and an oil of vegetable origin and not entirely from an oil of vegetable origin like the mother solutions according to the invention.